Pagans endure suffering for vanity
Tertullian is addressing imprisoned Christians, giving examples of pagans who voluntarily endured suffering for earthly glory or vanity.
I pass over the motive of glory for now. Vanity and a kind of sickness of mind have already trampled down all these same contests of cruelty and torture among men. How many idle men does vanity for arms hire out to the sword? Certainly they go down to face the beasts themselves out of vanity, and they think themselves more handsome for the bites and the scars. Some have even hired themselves out to the fires, so that they might run a fixed distance in a burning tunic. Others have walked about among the bulls of the beast-hunters with most patient shoulders. God has not admitted these things into the world without reason, blessed ones, but to exhort us now and to confound us on that day, if we shall have feared to suffer for truth unto salvation what others have pursued out of vanity unto destruction.
Latin
Omitto nunc gloriae causam. Eadem omnia saevitiae et cruciatus certamina iam apud homines affectatio quoque et morbus quidam animi conculcavit. Quot otiosos affectatio armorum ad gladium locat? Certe ad feras ipsas affectatione descendunt, et de morsibus et de cicatricibus formosiores sibi videntur. Iam et ad ignes quidam se auctoraverunt, ut certum spatium in tunica ardente conficerent. Alii inter venatorum taureas scapulis patientissimis inambulaverunt. Haec, benedicti, non sine causa dominus in saeculum admisit, sed ad nos et nunc exhortandos et in illo die confundendos, si reformidaverimus pati pro veritate in salutem quae alii affectaverunt pro vanitate in perditionem.